package lab02.test28;

import java.util.InputMismatchException;
import java.util.Scanner;

/**
 * Created by 阿阿阿阿豪丶 on 2017/11/21.
 */
public class Test {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Double radius = 0.1;
        System.out.println("请输入一个圆的半径，不要乱输");
        try {
            radius = scanner.nextDouble();
            System.out.println(radius*radius*3.14);
        }catch (InputMismatchException e){
            System.out.println("我再说一遍！不要乱输！");
        }

    }
}
